Science Homework Help

I’m working on a chemistry multi-part question and need an explanation to help me learn.

A small protein containing a disulfide bond (an intramolecular cross-link) was analyzed using differential scanning calorimetry and the thermogram shown below was obtained. There is a peak on the curve at 68 oC, called melting temperature, and the integrated area under the curve, corresponding to the enthalpy of the process, was calculated to be 240 kJ/mol.CP increases dramatically near 68 oC. Which statement is incorrect? [ Select ] [“Added thermal energy causes non-covalent bonds (H-bonds, salt bridges) in folded state to break“, “Added thermal energy is absorbed by the system without increasing temperature and is used for unfolding the protein.“, “Added thermal energy causes a chemical reaction, and the highest point corresponds to the transition state“]

What is ΔG at the melting temperature? [ Select ] [“ΔG > 0“, “ΔG = 0“, “ΔG < 0“]

Calculate ΔS at the melting temperature [ Select ] [“-0.70 kJ.mol-1.K-1“, “-3.53 kJ.mol-1.K-1“, “3.53 kJ.mol-1.K-1“, “0.70 kJ.mol-1.K-1“]

If the protein was treated with a reducing agent to break the disulfide bond and cause unfording, would you expect change to the entropy ? [ Select ] [“The entropy will not change“, “The entropy will decrease“, “The entropy will increase“]

If ΔHunfold was unaffected by the breakage of the disulfide bond, and ΔS unfold were to change by 115 J.K-1.mol-1, calculate the temperature Tm that corresponds to these conditions. [ Select ] [“39.6 degree Celsius“, “42.7 degree Celsius“, “21.5 degree Celsius“, “14.1 degree Celsius“]

Would you expect the protein to be folded or unfolded at 37oC at the conditions in the previous sub-question?